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arXiv · 0806.2809

Phase diagram and complexity of mode-locked lasers: from order to disorder

L. Leuzzi·C. Conti·V. Folli·L. Angelani·G. Ruocco
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Abstract

We investigate mode-locking processes in lasers displaying a variable degree of structural randomness, from standard optical cavities to multiple-scattering media. By employing methods mutuated from spin-glass theory, we analyze the mean-field Hamiltonian and derive a phase-diagram in terms of the pumping rate and the degree of disorder. Three phases are found: i) paramagnetic, corresponding to a noisy continuous wave emission, ii) ferromagnetic, that describes the standard passive mode-locking, and iii) the spin-glass in which the phases of the electromagnetic field are frozen in a exponentially large number of configurations. The way the mode-locking threshold is affected by the amount of disorder is quantified. The results are also relevant for other physical systems displaying a random Hamiltonian, like Bose-Einstein condensates and nonlinear optical beams.

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L. Leuzzi, C. Conti, V. Folli, L. Angelani, G. Ruocco. 2008-06-17. Phase diagram and complexity of mode-locked lasers: from order to disorder. https://doi.org/10.1103/physrevlett.102.083901

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